1. Field of the Invention
The invention relates to a system or a tool or an insert for the removal of the defect in a tooth or for making a cavity in a tooth.
There are various causes which justify the making, by machining involving the removal of material, of a cavity in a tooth and the repair of the tooth by means of a treatment of the cavity. Such a measure may be effected e.g. for aesthetic reasons to remove an unsatisfactory form of a part of the tooth. In most cases, however, these measures are carried out for repairing an unhealthy tooth, namely for removing a carious defect. A further reason for a measure as described above can also be the exchange of tooth fillings which are unsatisfactory for a variety of reason.
2. Description of the Related Art
In DE 42 09 191 A1 there are described a device and a process for the treatment of natural hard tissue with the employment of oscillating tools. With this known device, to make an occlusal cavity, a tool is used which has at its surface geometrically defined cutting edges or has cutting edges of non-defined geometric form such as adherent diamond grains, which make possible working of the material of the tooth, with the removal of material, with the oscillating movement of the tool. With the tool, there is made a cavity having an inwardly converging peripheral wall the cross-sectional size of which is a multiple of the cross-sectional size of the tool and the cross-sectional form of which differs substantially from the cross-sectional form of the tool. The tool is held releasably in a handpiece by means of a mounting device. The tool has a fluid outlet, at a spacing to the rear from the handpiece head which receives the tool, through which outlet a flow of fluid, e.g. water or a saline solution, can be directed at the treatment site and onto the tool for the purpose of cooling and rinsing. Measures for filling the cavity and treating the tooth are not described in this document. This known device and this known process are not only work and time consuming so far as the preparation of the cavity is concerned but also with regard to the usual methods of filling the cavity, whereby in this respect demands are made on the practicability of the preparation work and treatment work, on the thereby necessary manipulability, on the firmness and load bearing and on the lifetime of the treatment.
The above described treatment measures in a tooth occur not only in its occlusal region but also in its lateral and approximal region. In particular approximal preparations and treatments are difficult to carry out because of a neighbouring tooth and the thus resulting restricted accessibility, whereby there is a danger of damage to the neighbouring tooth.
The treatment of a cavity with a laboratory-prepared inlay is work-intensive and correspondingly expensive. Further, the tooth to be treated can be definitively treated only in a second treatment session and thus with "double time". To reduce the outlay involved in a treatment, it has already been proposed to use inlays manufactured at the place of treatment, as is e.g. possible with the so-called computer controlled milling of inlays. Further, it has already been proposed to use for the treatment of cavities prefabricated inlays, whereby likewise a treatment in only one treatment session and thus at a "single time" is possible. With such a measure, however, special preparation and treatment measures are needed which are again time consuming and involve complicated manipulation and are expensive.